Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

π Electron Effects on Chemical Shift: Overview

π Electron Effects on Chemical Shift: Overview

An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...

Molecular Orbital Theory II

Molecular Orbital Theory II

Molecular Orbital Energy Diagrams

MO Theory and Covalent Bonding

MO Theory and Covalent Bonding

The molecular orbital theory describes the distribution of electrons in molecules in a manner similar to the distribution of electrons in atomic orbitals. The region of space in which a valence electron in a molecule is likely to be found is called a molecular orbital. Mathematically, the linear combination of atomic orbitals (LCAO) generates molecular orbitals. Combinations of in-phase atomic orbital wave functions result in regions with a high probability of electron density, while...

Molecular Orbital Theory I

Molecular Orbital Theory I

Overview of Molecular Orbital Theory

Electric Dipoles and Dipole Moment

Electric Dipoles and Dipole Moment

Consider two charges of equal magnitude but opposite signs. If they cannot be separated by an external electric field, the system is called a permanent dipole. For example, the water molecule is a dipole, making it a good solvent.
Theoretically, studying electric dipoles leads to understanding why the resultant electric forces around us are weak. Since electric forces are strong, remnant net charges are rare. Hence, the interaction between dipoles helps us understand electrical interactions in...

The Energies of Atomic Orbitals

The Energies of Atomic Orbitals

In an atom, the negatively charged electrons are attracted to the positively charged nucleus. In a multielectron atom, electron-electron repulsions are also observed. The attractive and repulsive forces are dependent on the distance between the particles, as well as the sign and magnitude of the charges on the individual particles. When the charges on the particles are opposite, they attract each other. If both particles have the same charge, they repel each other.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Supramolecular purification of mono-adamantane mixtures <i>via</i> stabilized three-shell Matryoshka assemblies.

Chemical science·2026

Same author

Single-molecule kinetic exploration of functional sub-states in an evolving phosphotriesterase.

Nature communications·2026

Same author

Establishing the Fatty Acid Photodecarboxylase <i>Cv</i>FAP as a Platform for Photobiocatalytic Radical Transformations.

ACS catalysis·2026

Same author

Light-Induced Rotation of a Molecular Motor in the Confined Space of a Metal-Organic Nanocage.

Journal of the American Chemical Society·2026

Same author

Deciphering the molecular origin of the 19.3 eV electronic excitation energy of H<sub>3</sub><sup></sup>.

Chemical science·2026

Same author

Interphasic separation of <i>cis</i>/<i>trans</i> perylene-based nanographene isomers driven by selective encapsulation in a supramolecular cage.

Chemical communications (Cambridge, England)·2026

Search research articles

Related Experiment Video

Updated: Mar 8, 2026

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Published on: May 27, 2020

Electron correlation effects in third-order densities.

Mauricio Rodriguez-Mayorga¹, Eloy Ramos-Cordoba², Ferran Feixas³

¹Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, and Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain. ematito@gmail.com and Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, University of Girona, 17071 Girona, Catalonia, Spain.

Physical Chemistry Chemical Physics : PCCP

|January 26, 2017

Summary

This summary is machine-generated.

This study evaluates approximations for the third-order reduced density matrix (3-RDM) in electronic structure calculations. Current approximations show limitations, especially for systems with significant electron correlation effects.

More Related Videos

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

Published on: April 8, 2020

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Related Experiment Videos

Last Updated: Mar 8, 2026

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Published on: May 27, 2020

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

Published on: April 8, 2020

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Area of Science:

Quantum chemistry
Computational physics
Electronic structure theory

Background:

Electronic energy calculations often rely on reduced density matrices.
Approximations for the third-order reduced density matrix (3-RDM) are crucial but their accuracy varies.
N-representability conditions and the quality of the 3-RDM approximation significantly impact results.

Purpose of the Study:

To assess the performance of various 3-RDM approximations.
To evaluate how electron correlation affects the accuracy of these approximations.
To identify limitations of current 3-RDM approximations.

Main Methods:

Introduced a series of tests to evaluate 3-RDM approximations.
Utilized a model system, the three-electron harmonium atom, with varying electron correlation.
Compared different 3-RDM approximations under controlled conditions.

Main Results:

Identified limitations in commonly used 3-RDM approximations.
Demonstrated that accuracy deteriorates with increasing electron correlation.
Provided insights into the performance of 3-RDM approximations for correlated systems.

Conclusions:

Current 3-RDM approximations have significant limitations for systems with strong electron correlation.
Further development of 3-RDM approximations is needed for accurate electronic structure calculations.
This work provides a benchmark for future studies on reduced density matrix methods.